Critical transitionCritical transitions are abrupt shifts in the state of ecosystems, the climate, financial and economic systems or other complexdynamical systems that may occur when changing conditions pass a critical or bifurcation point. As such, they are a particular type of regime shift. Recovery from such shifts may require more than a simple return to the conditions at which a transition occurred, a phenomenon called hysteresis.
Ecological extinctionEcological extinction is "the reduction of a species to such low abundance that, although it is still present in the community, it no longer interacts significantly with other species". Ecological extinction stands out because it is the interaction ecology of a species that is important for conservation work.
Ecological resilienceIn ecology, resilience is the capacity of an ecosystem to respond to a perturbation or disturbance by resisting damage and subsequently recovering. Such perturbations and disturbances can include stochastic events such as fires, flooding, windstorms, insect population explosions, and human activities such as deforestation, fracking of the ground for oil extraction, pesticide sprayed in soil, and the introduction of exotic plant or animal species.
EcosystemCommunity of living organisms together with the nonliving components of their environmentLeft: Coral reef ecosystems are highly productive marine systems. Right: Temperate rainforest, a terrestrial ecosystem.An ecosystem (or ecological system) is a system formed by organisms in interaction with their environment, where the biotic and abiotic components are linked together through nutrient cycles and energy flows. Ecosystems are controlled by external and internal factors.
Disturbance (ecology)In ecology, a disturbance is a change in environmental conditions that causes a pronounced change in an ecosystem. Disturbances often act quickly and with great effect, to alter the physical structure or arrangement of biotic and abiotic elements. A disturbance can also occur over a long period of time and can impact the biodiversity within an ecosystem.
Regime shiftRegime shifts are large, abrupt, persistent changes in the structure and function of ecosystems, the climate, financial systems or other complex systems. A regime is a characteristic behaviour of a system which is maintained by mutually reinforced processes or feedbacks. Regimes are considered persistent relative to the time period over which the shift occurs.
Tipping points in the climate systemCritical thresholds in climate scienceA map showing global and regional tipping elements: if the global temperature increases past a certain point (color-coded for temperature thresholds), this particular element would be tipped. The result would be a transition to a different state.In climate science, a tipping point is a critical threshold that, when crossed, leads to large, accelerating and often irreversible changes in the climate system.
HysteresisHysteresis is the dependence of the state of a system on its history. For example, a magnet may have more than one possible magnetic moment in a given magnetic field, depending on how the field changed in the past. Such a system is called hysteretic. Plots of a single component of the moment often form a loop or hysteresis curve, where there are different values of one variable depending on the direction of change of another variable.
Ecosystem healthEcosystem health is a metaphor used to describe the condition of an ecosystem. Ecosystem condition can vary as a result of fire, flooding, drought, extinctions, invasive species, climate change, mining, fishing, farming or logging, chemical spills, and a host of other reasons.Critical loadIn the study of air pollution, a critical load is defined as "a quantitative estimate of an exposure to one or more pollutants below which significant harmful effects on specified sensitive elements of the environment do not occur according to present knowledge". Air pollution research in relation to critical loads has focused on nitrogen and sulfur pollutants. After these pollutants are emitted into the atmosphere, they are subsequently deposited into ecosystems.
Nonlinear systemIn mathematics and science, a nonlinear system (or a non-linear system) is a system in which the change of the output is not proportional to the change of the input. Nonlinear problems are of interest to engineers, biologists, physicists, mathematicians, and many other scientists since most systems are inherently nonlinear in nature.
Environmental issuesConcerns and policies regarding the biophysical environmentWater pollution is an environmental issue that affects many water bodies. This photograph shows foam on the New River as it enters the United States from Mexico.Environmental issues are disruptions in the usual function of ecosystems. Further, these issues can be caused by humans (human impact on the environment) or they can be natural.*As an Amazon Associate I earn from qualifying purchases.